Combustion chamber for steam boilers



Oct. 19, 1937. l J. c. JQHNSON 2,096,586

COMBUSTION CHAMBER FOR STEAM BOILERS Filed July 8. 19:55 2 sheets-sheet1 uBlgEll-VOR v Another object of the invention is to provide'for lconcentrick with; and disposed'- y Patented Oct. 19, 1937 I l 1 li; n di,

Annueation'iJulya 1935; sei-M Nef-130,269 f This invention relates -togsteamboilers.. and A head I0 is welded into the; upperjend of theparticularly to the construction of the fuel comshell 9 in the jsamekmanner as -theheads-landl bustion chambers thereof. l .e-are-mounted,1andlboth'theiheadsgand Mare AIt is an object of theinvention to provide for provided.withaplurality of spaced vaperturesin. 1 5 concentration of the hot gases in the combustion which, .aresecured,-.by rolling or, welding'in -th 5 chamber of a boiler so as toinsure'. that combusf manner well-known in the boiler-making art. tionof the fuel issubstantially-complete before tubesyfl I.- Toi-,provide'.forstabilizationsof the gases contact thesurfaces through which-thecombustion chamber, studsiiz arePrQvided securheat is conveyed to thewater-.inthe boiler. ing the former.to-the,s1'iellff4.;- p 1Quttiieshell.`r ;10 'reflecting heat inthe lrebox of a boiler and. fois.a sheet-metal jacket 'llwhichserves t9. main y cusing'it at a pointadjacent the burner` sothat tain a 4layerfoi sui table hea,i.`insulation` l 4 against unatomized particles of fuel dischargedfr'omthethe shell, and a domefi, ofrefractorymateriaL burnerA win beeeempmteiyfdisintegrated and ig- -whiehiseeovered by'a sheet maternita-iiv-is;di-s-v "u y p Y y posed on'the upper-head-:l' The di'imefialifo--pA15 Afurther object of-y the invention `is to Vprovide vided with acentral aperture L iL] closedgby 1a 1 an improved reboxfor `boilers bymeans of` which covercj lffthrough which inspection;v or clcls .niijigvmaterial economies in fuelv consumption may-be ofthetubes1H;maybicompllshedfMld@pas e 35 incorporating the principlesofthey invention. combustion chambenf;

eiiected. sagel I9 connectsethefonen. space.g20; above theup Stillanother `object of .theiinvention-is to pro- ...per .ends 0f the, tubesWith 1B m16 CQXllneGtOlT-U vide an improved rebox. constructionforboilers ...through whichthe products of 1 combustion Amay which, bymeans of heat reilectiomga'ssists Y th be led outof the .building burnertov operate on low gravity fuel. x '-:Securedtothe-shell,.4,-overfthe'open endofthe y The invention possesses otherobjectsand'feacombustion chambertube 11, by,fxnean s ,o f the tures ofadvantage some ofrwhich together with screws 22, is a plate 23 having .aeen tral aperture 25 'the foregoing, wiu be pointed. 'out inthe-detailed-24 therein in which-ismounted almrner..` a

description of the invention following, however it burner is.preferablyl of the ,rotary; t ype,,

is tobe understood that the inventionis notto be crudfoil as fuel,` andhaving.agsuitableuelab .limited tothe specific embodiment shown-andomzer 26 disposed within a tubular airnozzlel, 30 described as variousembodiments thereof maybe through which a continuousblastof air, fromanv 30 employed within theV scope of the appended limpeller containedwithin the burner hollsing..is claims.

, i dischargedsoas to create a combustible-mixture, .Referring Vtothedrawings: with the particles of fuel discharged.byl the at- Figure l isa vertical sectional view of va boiler .omizenand `t0 COIlVeY th? fllelfvgtileSQlntO-ftiie Figure 2 is avhorizontal sectional view oftheWithin the tubefli of the cmbustion'chamber boiler. The plane ofsection, Iin which this-view is a fire-box, constructed lof"refractorymaterial, is taken is indicated by theline,2-2 of Figure 1. andcomprising Ian upper sectionfZQ and'aflower Figure 3 is a horizontalsectional .view of the fseCtiOn 29J'Qint2d ifi a' p1?1'1"',indi}ted',bylthe'line 40 boilerltaken through thelcomhustion chamberas 3B.Both o'f theiire-boxj sections terminate'. atY 40 indicated by theline:3-f3 'of Figurel. therouter ends, `ashortdistance.from the inner.In detail, my invention is particularlyadapted 'Surface 0f the plate 23. vS0 fas $0 Il'OVite `all l8411' to the smaller boilers, of the typeshown inlig-r space Stand, at their inner ends, substantially at ure l,which are employedinhomes for the genthe'centerline of theilrt1Caltubu1arD0rt1nlof eration of steam, or hot water, for heatingpurthe combustion'chamber; f i-`' f poses, in which a cylindrical shell4 is -provided "The: upper section 28-is providedwith a collar with anupper head 5 and a lower head 6 welded 412, Substanllly'incontact-Withfthebore 0i' the into the ends thereof.A tube 1,.the:rest ofthesection fbeing'ofglesser-` ra- A combustion chamber is provided,comprising f' dillS and; convergent axially so 'as to rprovide-a` 50 ahorizontally disposed tube 1 which is welded at space 33 between thesurface of the sectionand 50 n one end into a large aperture formedadjacent the inner surface of the tube and the -lower secthe lower endof the shell 4, and which is mitered tion is also narrowed, at itssides, so as .toprovlde f at its inner end and joined along the line 1by spaces 34 between it and the vcombustion Chamber f weiding s, with avertically/ disposed tube s pesiwens. This 'construction provides furtheexpog tioned concentrically with, and within, the shell 4.' sure of alargeportion of the surfaces of the tubes 55 1 and 9 to the hot gases inthe combustion chamber.

Both sectionsare provided with recessedcenshutter-'31 is provided, overan aperture 3B inv the plate 23, so that air may bei permitted to enterA the fire-box, through the passages described, in regulated amounts.The outer end of `each nrebox section is provided with abutments 39which contact the rim I0 about the plate aperture 2,4 and isolate thefire-box from theair space" 3l."

reflector, also constructed of refractory material and comprising abody4i' provided with a' concave surface I2 facing` the burner and afoot I3extending, for the purpose of stabilizing the'body ll', along the-bottomof the tube 1, and also in4 contact with lthe-'end ofthe-lowerre-boxsection so as to maintain thebody 4I firmly against theyrear wall'of the vertical tube 9.1 Portions of the lower section 2f9';fas isindicated by the y dotted lines are Acut away-so, as wasexplainedabove,

the hot gases are permitted to contact thelower inner surface ofthetube`1.

Let usnow consider the' operation of the boiler particularlyl actionwhich occurs 'in the Vcombustionchai'nber thereof. In most`boilers ofthis type it is necessa'xythat the burner run for a` conside'rableperiod of time before satisfactorycombustion occurs,` this being due,particularly? if the fuel voil used isfof low gravity, zto" theinability of thebrnerr to thoroughly atomize the fuel,thereby'rsultingfin a Allame having*considerablyA less thanthemaxlmum'pos'sible'temperature, and to thefalcl'ftl'iat"thev alnei'sibei'ng DIOJected into .a vcoldcombustionchamber in whichthere Vareno v'hot surfaceswhichwill disintegrate the heavier fuel particles. Theresult'therefore is that considerable incompletely consumed fuel will beexhausted through the flue during the time that it takes the combustionlchamber to attain the temperature necessary to-fthoroughly vaporize thefuel and effect eilicient combustion thereof. The

amount-of loss in fuel, underv such conditions, is obvious. 'l w" f y iv In the boilerof `my invention-these objections have,-to yafgreatextent, been overcome. As, soon as `the vburner *25,l is lighted theflame cone'projected thereby into the nre-box will, due to thediminishing 4boreof the fire-box, be prevented -f so from expanding andcooling and willbe discharged from' the end of the fire-box against theconcave face CE2 of the reflector.

While` some of the .gases ,Willfescape radially through 'the gapbetwe'en'theend of the firebox and the face 4of the'reector and ,becarried through the flue, most 4of the heat will be reflected back Aintothe ilre-box where itlwill act to raise the fiameteniperature and causevaporization of any heavy fuel particles whichmaybe discharged by theburncr.-;.The result therefore is that the flame temperature inthe're-box iscontinually being supplemented bythe heat4 reflected fromthe surface, thereby provi'ding'for more rapid and complete combustionof the fuel being dis# charged from the burner.

It is therefore obvious that by the use of the reiiector actiondescribed above in the combustion' chamber of a boiler, or other devicerequiring l which are sturdilyconstructed and which, if they j4 becomefracturedA orpartially consumed, may bel Spaced from the open end of theflre-boxis a replaced by removing theA plate 23, inserting the newsections, and replacing the plate, no cementingin, ror other means ofattachment being necessary to hold the parts in place.

In conclusion, the combustion ,chamberl conlstruction describedabove hasproven a distinct Aadvance in theart,it being proven by comparativetests that the operating efliciency of a boiler so equipped far exceedsthat of others ofy its type. w-r-ciaimz Y l I 1. In a boilervhavingfacombustion chamber, a

1 fire-box withnsaid combustion chamber comprising-a refractory member.having a central-tapered bore therein open at its smaller end, an endwall closing theV large yend of said bore and providedk with anaperture-therein through which ay burner nozzle may project :into saidbore, and a. blockof refractory f material spaced from vsaid, refractorymember" and .overlying the kopen' end of the, bore thereof, said blockhaving a concave surface fac- V,ing the open end of'saidbore,` and saidconcave surface having its center of curvature lying-on the central axisof said bore. c, ya. t i.

2. In a boiler having a combus on chamber, a hre-box Within fsaidcombustion chamber comjfprising. a refractory member havinga centralfftaperedgboretherein' open at itsssmaller end, an

end wall closingxt-he-.la'rge end of said ,bore and provided with anaperture therein` through which a burner nozzle may project intosaidboreand a blockof refractory.,V material spaced from saidrefractorymember, and overlying the openend of the bore'y thereof, saidblock having a concave surface facingthe :open end 'lof-said bore, and-said concavesurface having its center of curvak turelying. within saidbore and on they central axis thereof.

3. In a boiler having a combustionchamber, a

'fire-box. within said .combustion .chamber comprising a'refractorymember having av central tapered bore therein open at its smaller endand an opening intermediate theends thereof through which a current oflair 'may be admitted to said bore, an end VWalrclosing` the large end ofsaid bore having an .aperture-therein through which a burner nozzle mayproject into said bore, and

1 a block of refractory material overlying and ture lying within, andon'itheraxisof, said bore adjacent said burner nozzle.Y

L yJESSE C. JOHNSON.

